var oWho = document.querySelector('#who')
var oWhom = document.querySelector('#whom')
var oWhat = document.querySelector('#what')
var oTbody = document.querySelector('tbody')

document.querySelector('button').onclick = function() {
    var who = oWho.value.trim()
    oWho.value = ''

    var whom = oWhom.value.trim()
    oWhom.value = ''

    var what = oWhat.value.trim()
    oWhat.value = ''

    console.debug('谁: ' + who)
    console.debug('对谁: ' + whom)
    console.debug('说什么: ' + what)

    // 组成 <tr><td who><td whom><td what></tr>
    var html = `<tr><td>${who}</td><td>${whom}</td><td>${what}</td></tr>`

    oTbody.innerHTML += html
}